Electric brake.



No. 695,l44. Patented Mar. ll, I902.

F. E. CASE.

ELECIR IC BRAKE.

Application filed Apr. 4, 1898.) (N 0 M 0 d e l 2 Sheets--Sheet I.

No. es5,|44. Patented Mar. u, l90'2.

F. E. CASE.

ELECTRIC BRAKE.

Application filed Apr. 4, 1898 (No Model.) 2 Shets-Sheet 2.

9 NV NT R- FEank E.Case,

Unrrnn Srains ATENT rrrcn,

FRANK E. CASE, OF SCHENECTADY, NEW YORK, ASSIGNOR TO GENERAL ELECTRIC COMPANY, A CORPORATION OF NEW YORK.

ELECTRIC BRAKE.

SEECIIEIGATION forming part of Letters Patent No. 695,144, dated March 11, 1 902.

Application filed April 4, 1898. Serial No. 676.302. (No model.)

To ctZZ whom it mayconcern:

Be it known that I, FRANK E. CASE, a citizen of the United States, residing at Schenectady, in the county of Schenectady, State of New York,have invented certain new and useful Improvements in Electric Brakes, (Case No. 672,) of which the following is a specification.

My present invention has for its object to provide a system of trainer motor-car braking particularly useful in connection with electrically-propelled apparatus.

My invention contemplates the use of a mechanical brake applied by the action of an electric or other motor, the gearing between the motor and the brake being preferably arranged in such a manner that the friction of the gearing will be sufficient to hold the brake in whatever position it may at any time be left by the stoppage of the motor. I may, however, accomplish the same result by artificially increasing the friction of the device whenever the motor is stopped, as by the operation of a friction-brake. It will be obvious that each motor may apply one or more brakes, as desired, and that the motors and brakes may be placed upon the car or train wherever necessary.

One of the features of my invention consists in regulating the braking-motor by contacts on the main motor-controller, these contacts being so arranged that at the proper point in the movement of the controller the braking-motor will be energized to apply the brake-shoes and at another controller position the brake-shoes will be released, preferably by reversal of the braking-motor. The latter operation should be effected at or about the time of starting the car or train. The contacts may therefore be so placed as to reversely connect the brake-motor at the first power-point of the controller, or they may be arranged to thus connect the said motor before the current is admitted to the propelling-motors. It will generally be convenient to utilize the trolley-current for operating the braking-motor, but in the application of the brakes the'motor may, if desired, be operated by current from the propelling-motors operating as momentum-driven generators.

Under some conditions a storage battery may be utilized to advantage.

My invention also provides for a motor-car or train equipped with electric or otherpower braking means, whose braking effect depends upon the momentum of the car, a means for stopping the car and holding it on grades after the speed has become so low that the electric or other power braking means has ceased to act or to have suflicient adherence to hold the car.

For the purposes of my invention I use a small motor, to which is connected a windingdrum, taking up the chain of the ordinary brake-rigging and applying the shoes. The motor acts, preferably, through a worm-gear, so that after it has once wound up the drum current may be turned off while the car stands. In order to unwind the chain and release the brakeshoes, the motor will be operated in the reverse direction.

\Vhile I have used the trolley-current in the way pointed out, it is manifest that any convenient source of current might be cmployed-for instance, as already stated, I might employ a storage battery, which would be charged from the trolley-line during the running of the train. This could be done by putting the battery in shunt to a part of the motor-regulating resistance, as in the patent to Edward M. Hewlett, No. 589,893, or in any other convenient way. With the battery thus energized the motor may be operated from it to apply and release the brakes or for either one of these purposes without departing from my invention. Ordinarily the simplest and most apparent application of the invention will be to use the trolley-current.

The accompanying drawings show an embodiment of the invention.

Figure l is a plan view of the trucks of two motor-cars equipped with my invention and is to be taken as typical of any number of cars which may be convenient. Figs. 2 and 3 are end and side elevations, respectively, of a suitable motor and winding-drum. Fig. 4. is a diagrammatic development of a suit able controller, showing contacts which illus trate my invention. Fig. 5 is a diagram of a modification in which a storage battery is used. Figs. 6 and 7 show a train equipped with the invention.

In Fig. 1, A B are the two trucks equipped with the propelling-motors O 0. Each of these trucks is provided with the usual brakerigging 'D, connected by chains F with the winding-drums of the respective motors E E. The usual brake-shoes of electric type are provided, as indicated at H II. The ordinary brake-shoes applied to the tread of the wheel are shown at h on both the cars. The controlling device is indicated at K.

Fig. 2 shows an end elevation of one of the brake-motors. One of the gears, or, as it is commonly called, the pinion, of the motor 6 drives another geare. Upon the shaftof the latter is a worm e connecting with the wormgearf of the winding-drum. The rotation of the drum acts to draw up the chain F of the brake-rigging, the levers of which are shown in plan in Fig. l and work in the ordinary way, well understood in the art, not requiring description. The operation of so much of the device will be readily apparent.

In Fig. 4 a proper controlling device is shown developed. The fixed contacts are indicated by the circles and the moving contacts by the rectangles. The connections for regulating the propelling-motors will not be particularly described, as they form no part of my invention and in general are well known in the art. It may be said, however, that the contacts upon the left form the braking portion of the switch and those upon the right are designed to regulate the propellingmotors C C from rest to full speed by the ordinary series-parallel methods; but my invention may be well applied with other forms of motor-regulating switch. The general principle of the switch here chosen for illustration is that of the patent to Potter, No. 524,396, though modified by the addition of the brake contacts. The brake-motors are illustrated diagrammatically at E E. In the operation of the controller when the contacts upon the left are turned the usual electric brake-circuits would be completed until the contact 1, by which the trolley-current enters the controller, reaches the contact 1 on the left. At this time all of the contacts 1 to 4 are upon the two contacts 1 3 Current therefore passes from the trolley T to contact 2,f througl1 the armatures A and A of the brake-motors in multiple, back to contact 3, to contact 4, and through the fields F F in multipleto ground at G. The motor-armatures are thus rotated and the brake-shoes h would be applied. When this has been done, the controller may be turned to the off position until it is desired to start the car. At the first operative position of the motor-regulating contacts, shown on the right of the switch K, the trolley would touch contact 1, and then current would pass to the contact 3, passing through the armatures A A in multiple, but in the reverse direction, and then returning to contact 2 pass to 4, and

through the fields F F to ground, thus reversing the motors. Of course as soon as the brakes are released the controller. may be further rotated to propel the car, thus breaking contact with the plates 2 to 4 and cutting out the motors E E at or before the time when the motors C C are broughtinto circuit. The motors E E may be very small and designed for high current capacity for a short time. In fact, they may be of such size that if kept in circuit forany great length of time they would be destroyed, and yet be used for my invention without risk, as they may be of high counter electromotive force and run Very fast, winding up the chain with great rapidity. The static friction of a car at rest being great the brake-shoes h need only be slightly applied to hold the car even on a considerable grade.

Where other forms of gearing than the worm are to be used, a modified form of motor may be desirable. My invention, however, does not reside so much in these engineering details as in the general idea of a controlling device for the propelling-motors, with contacts arranged to operate a motor for wind-' ing up a brake-chain when applied in one direction and for releasing it when applied in the other. and power cylinders of the controller are in different switches, as is sometimes the case, the contacts for applying the motors in one direction may be, if desired, in one switch and for reversing them may be in the other. Of course suitable resistances may be used in any desired relation. I have not thought it necessary to illustrate these details. I In Fig. 5 I have shown a modification in which a storage battery may be employed, the connections of which will be apparent from an inspection of the figure. Only one of the motors E is shown; but the application to another or other motors will be readily apparent. In connection with this figure I have also shown that instead of using a worm-gear other forms of gearing might be used. The band-brake M may be applied to the motor, being actuated by a lever O, pivoted ate, the band-brake being applied by a spring 0.

I When, however, the motor-armature A is to be actuated, the current would pass around the coils of the electromagnet N, releasing the lever O and slacking the band, so that the motor might rotate so long as the current was on. As soon, however, as current ceases, the brake is applied and the motor quickly stops. In some cases this may be. preferred to the worm, as it avoids the inherent friction of the latter device and does not waste current in the magnet N, the coils of which are only in circuit while the motor is running.

In Figs. 6 and 71 show the application of the invention to a train system composed of a number of independent units-that is, of carseach of which is provided with its own propelling-motors and a controller regulating these motors, with master-controllers located at different points along the train and each controlling the operation of allof the lnotor controllers. This is a form of device which is coming into use in the artand upon Which I have pending applications. I therefore make no claim in this application, except in so far as the application of the present invention is con cerned, to such a system. In these figures A B B are the motor cars or units of the system. K K, &c., are the motor-controllers. Q Q &c., are the master-controllers, situated at convenient points. The arrangement is best understood from Fig. 7, the same referenceletters being employed. Each of the mastercontrollers Q acts to control the rotation of pilot-motors, so-called, P P, the latter operating the controllers K K simultaneously in the same direction. The different trolleys T T, which are here illustrated as suitable for a third-rail system, are connected in multiple to the train wire T'W. All of the pilotmotors are also connected in multiple to the set of wires illustrated. Then, forinstance, the controller Q is rotated, its two upper contacts are connected by the moving contact on the left and its two lower ones similarly connected. The circuit would therefore be from the trolleys to the upper contact of the trolley Q to the next contact in order, then through the armatures of the motors I P in multiple, then back to the third contact of the controller, then to the fourth contact, then through the fields of the motors in multiple to ground. The controlling devices K K" would be rotated so long as the motors revolved, and when the train had come to full speed the controller Q could be turned off.

When it is desired to stop the train,the controller Q may be oppositely rotated. By tracing the connections it will be found that the relation of armature and fields in the pilotmotors is reversed, so that they run backward and rotate the controlling device either to the off position, as illustrated in Fig. 4, or, passing still further, to the position in which the brakes are applied, and finally to its position in Which the ordinary brake-shoes are applied by the motors E.

It is manifest that With such a system the entire braking may be done by the motors E,.

if desired. Of course the operation of any of the other master-controllers, they being all connected in multiple,would be identical with thatof the one described.

What I claim as new, and desire to secure by Letters Patent of the United States, is-

1. A brake system for an electrically-propelled car or train, comprising a propelling motor or motors, a brake, a motor for applying the brake, and a controlling device having contacts for regulating the propelling motor or motors, contacts at one of its positions for actuating the brake-motor in one direction and contacts at another position for actuating the brake-motor in the reverse direction.

2. A brake systeinfor an electrically-propelled car or train, comprising brake-shoes on some or all of the cars, an independent, rotary electric motor or motors for actuating said brake-shoes, propelling-motors, a 0011- trolling device for the propelling-motors, and contacts on the said controlling device for connecting the brake motor or motors in circuit for either direction of rotation.

3. An electric-brake system for a car or train, comprising a rotary motor for each car, a drum actuated by each motor and applying or releasing the brake-rigging in accordance with the direction-of rotation of the motors, propelling-motors for the car or train and a controlling device regulating both the propeliing and the brake motors, the controlling device having contacts at one of its positions for driving the brake-motors in one direction, and contacts at or about the first power-point for reversing them.

4. An electric-brake system for a car or train, comprising a rotary brake-motor on each car, a drum actuated by each brake-motor to apply or release the brake-rigging in accordance with the direction of rotation of the said motors, a braking device for each of the motors, released or applied by turning on or off of current, propelling-motors for the car or train, and a controlling device regulating all the motors.

5. A controlling device for an electricallypropelled car or train, equipped With propelling-motors and separate braking-motors, having contacts for regulating the propellingmotors, braking contacts utilizing the propelling-motors as generators, and a contact or contacts on the brake side for driving the brake-motors in one direction to apply the brakes, and other contacts for driving them in the opposite direction to release the brakes.

6. The combination of a number of motoroars united in a train, each car having propelling-motors, rotary braking-motors, and a controller for all the motors of the car, and being a complete unit capable of individual operation, With master-controllers at different points in the train, and means regulated by the master-controllers for simultaneously operating all the motor-controllers.

In witness whereof I have hereunto set my hand this 1st day of April, 1898.

FRANK E. CASE.

Witnesses:

B. B. HULL, M. H. EMEnsoN. 

